The extreme limit of human noise tolerance is:

DSSSB 14 August 2024

Applied Physiology

Easy

Appeared in: DSSSB 14 August 2024

Explanation

The extreme limit for human noise tolerance before immediate pain and damage occur is approximately 140 decibels (dB).
This level is known as the threshold of pain.
Sounds at this intensity, such as a jet engine at close range or a firecracker, can cause immediate and permanent damage to the auditory system.
The Occupational Safety and Health Administration (OSHA) notes that impulsive or impact noise should not exceed a 140-dB peak sound pressure level.

Option A: A sound level of 210 decibels is far beyond the threshold of pain and would be catastrophic, likely causing severe physical trauma to the entire body and potentially being lethal. For reference, a rocket launch is around 180 dB.
Option B: A level of 70 decibels is equivalent to the noise of a vacuum cleaner or normal conversation. It is well within safe listening limits and is not an 'extreme limit'.
Option D: A level of 35 decibels represents a very quiet environment, similar to a whisper or a quiet library. It poses no risk to hearing whatsoever.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Human noise tolerance and the decibel scale as background academic context rather than a clinical decision trigger.
Nurses, particularly in occupational health, must educate workers about the dangers of Noise-Induced Hearing Loss (NIHL) and the importance of using personal protective equipment (PPE) like earplugs in noisy environments (e.g., factories, construction sites).
In clinical settings like ICUs, constant alarm sounds can exceed safe levels, contributing to patient delirium and staff burnout. Understanding noise levels is crucial for creating a healing environment.
What if? If the question asked for the level at which prolonged exposure (e.g., an 8-hour workday) becomes a risk requiring action, the answer would be 85 decibels, which is the standard action level for OSHA's hearing conservation programs.

How to Approach the Question

First, identify the key terms in the question: 'extreme limit' and 'noise tolerance'. This indicates you are looking for the maximum level of sound a human can withstand before pain or injury.
Second, recall or reason about the decibel scale in relation to common sounds. A whisper is very low (around 30 dB), a conversation is moderate (around 60 dB), and a jet engine is extremely loud.
Third, evaluate the options based on this mental scale. 35 dB and 70 dB are clearly too low to be an 'extreme limit'.
Fourth, differentiate between the two high values: 140 dB and 210 dB. 140 dB is widely cited as the threshold of pain. 210 dB is an exceptionally high value, far beyond levels like a rocket launch (180 dB), making it an unrealistic 'tolerance' limit.
Finally, select the option that corresponds to the established threshold of pain for human hearing.

Concept Tested & Keywords

Qd5_3M3r0Lj9T67nbMDYSJ

E6 Medicine Harrison 22e Part 1 p. 292-294

E6 Psychology Baron Misra 5e Part 1 p. 125-127